Add an autoclose option in "Alert"

[apesme]

Is there a possibility to add an autoclose option in Alert ?
something like this :

<alert ng-repeat="alert in alerts" type="alert.type"  close="alert.close()" autoclose="10000">{{alert.msg}}</alert>

and in the directive, have something like this :

if (autoclose) {
$timeout(alert.close, autoclose);
}

[RobJacobs]

@laac This pull request #2854 adds that feature.